To
make the most of the educational and research opportunities provided
by the Lewis Center, Oberlin partnered with the U.S. Department
of Energys National Renewable Energy Laboratory (NREL) to
develop a comprehensive data-monitoring system. Funded in part by
a grant from the Andrew W. Mellon Foundation,148 sensors were installed
that collect data on the flow of energy and matter. These data allow
us to assess the instant and long-term changes in the buildings
performance.

We recently installed the first of several computer monitors in
the atrium that display real-time data to make transparent the relationships
between building activity, environmental conditions, and resource
use. Observers can now witness how clouds passing over the sun affect
energy production by the solar cells, how heating and lighting decisions
affect total energy consumption, and how biological activity in
the Living Machine affects water quality. The same real-time data
is posted at www.oberlin.edu/~envs/ajlc/AJLCdefault.htm,
with a more detailed explanation of the technology incorporated.

Work on the energy portion of the monitoring system was completed
in March 2001. This past spring, therefore, we were able to calculate
a complete annual budget for energy production and consumption.
Because each building is unique, and because this past winter was
relatively mild, comparison of a single years data with other
buildings should be made cautiously, but the story so far is encouraging.
Gross direct energy consumption in the Lewis Center between April
2001 and April 2002 was 30,000 British Thermal Units (or BTUs) per
square foot. This represents 38 percent of the national average
reported for educational buildings, 36 percent of the consumption
values for nine other Oberlin buildings (data from a 2000 study),
and just slightly lower than those values reported for Vermont Law
Schools Oakes Hall, which is often cited as a standard for
energy-efficient academic buildings at our latitude.

The production of energy by the Lewis Centers solar panels
met approximately 53 percent of the buildings energy demand.
Adding this solar energy production to the equation lowers the Lewis
Centers total net energy consumption to just 14,000 BTUs per
square foot, which amounts to 41 percent of Vermont Law School and
just 17 percent of the average for Oberlin buildings. Of particular
note is the effect of natural lighting and high efficiency fixturesin
spite of the Lewis Centers popularity for evening classes
and events, it used only 28 percent of the light energy reported
for typical educational buildings and 23 percent of the light energy
consumed by other Oberlin College buildings.

Although the data suggest that the building is already exhibiting
exemplary performance, further improvement is possible. Fifty-five
percent of the energy used last year was for heating, ventilation,
and air conditioning. Professor John Scofield, in his accompanying
column, correctly points out that several errors were made in the
design of the heating system: boilers were used where heat pumps
should have been installed, and heat pumps were mismatched with
the temperatures of the ground water supply. According to our colleagues
at NREL, errors of this type are unfortunately quite common, particularly
in green projects that combine innovative technologies that are
unfamiliar to most engineers.

Oberlin is still in the process of optimizing the buildings
energy performance by changing the heating equipment and the control
strategy. For example, simply by shifting reliance from a boiler
to heat pumps, we achieved a 50 percent decrease in heating energy
in March 2002 relative to March of 2001 (calculated differences
in energy requirements were normalized for temperature differences).
Twenty-nine percent of this past years heating energy was
consumed by an electric boiler that has now been replaced with a
more efficient heat pump. Although corrections such as these do
add unanticipated costs (environmental as well as financial), they
should be viewed in the context of a building that serves as a laboratory,
not just for Oberlin students, but for the impressive stream of
architects and designers who visit each year. And as with most innovative
endeavors, the community will likely learn as much from mistakes
as from immediate successes. We anticipate that changes currently
under way, combined with further upgrades as new technologies emerge,
will result in a steady improvement in performance in the coming
years.